test-pathconflicts-basic: use treestate

Summary:
For treestate+fsmonitor case, `dirstate._map.get(path)[0]` could be `?`.
It's a new condition that the pathconflict code path didn't expect. So let's
update pathconflict checker to work with treestate+fsmonitor.

Reviewed By: DurhamG

Differential Revision: D8842393

fbshipit-source-id: 4679e23f37310bea18c34676231baa4854de1611

mercurial/dirstate.py

@@ -464,7 +464,7 @@ class dirstate(object):
                 if self._map.hastrackeddir(d):
                     break
                 entry = self._map.get(d)
-                if entry is not None and entry[0] != "r":
+                if entry is not None and entry[0] not in "r?":
                     raise error.Abort(_("file %r in dirstate clashes with %r") % (d, f))
         self._dirty = True
         self._updatedfiles.add(f)

tests/test-pathconflicts-basic.t

@@ -1,3 +1,7 @@
+Turn on treestate
+
+  $ setconfig format.dirstate=2
+
 Path conflict checking is currently disabled by default because of issue5716.
 Turn it on for this test.